This invention relates generally to steps for motor vehicles such as campers, trucks, and the like, and, more particularly, to automatically extendable and retractable steps for mounting and alighting from such vehicles.
On many motor vehicles a retractable step is provided beneath a door to assist a passenger or driver in mounting or alighting from the vehicle. Such a step is particularly useful on recreational vehicles, campers, trucks and the like, where the door of the vehicle is located at a height above the ground such that it is difficult or inconvenient for a person to step directly from the ground into the vehicle, or from the vehicle to the ground.
On such a vehicle, it is highly desirable for the step to be retractable so that it does not project from the wall of the motor vehicle when the vehicle is being driven, and it is particularly desirable for such a step to be automatically extendable and retractable. One way in which this has been accomplished is by providing a manually operable switch or valve in the vehicle for electrically or pneumatically retracting or extending the step. This arrangement is characterized by the disadvantage that people often forget to retract the step, and when the motor vehicle is operated with the step extended, severe damage is likely to be caused to either an object with which the step may come in contact or the step, or both.
Moreover, with an electrically operated step, a lockout device must be provided for permitting operation of the step only when the engine of the vehicle is running. If an electrically operated step is not provided with such a lockout device, frequent operation of the step, as for example where the switch is door operated, will cause undesirable discharge of the storage battery of the vehicle. If the step is extended and retracted pneumatically, as for example by the vacuum created in the intake manifold of the engine of the vehicle, the step can only be operated when the engine is running. In both of the above examples, the step will remain in the position it occupies when the engine is turned off.
Accordingly, there has existed a need for a safe, convenient and effective step for a motor vehicle which will automatically extend or retract to the desired position regardless of whether the engine of the vehicle is running and without requiring the manual operation of a switch or a valve. As will become apparent from the following, the present invention satisfies that need.